1. Field of the Invention
The invention relates to exercise equipment, more particularly to an elliptical exercise apparatus.
2. Description of the Related Art
FIGS. 1 to 3 illustrate a conventional elliptical exercise apparatus 1 which was disclosed in Taiwanese Utility Model Publication No. 414094 and which was invented by the applicant in February, 2000. The elliptical exercise apparatus 1 comprises a main frame 11, two swing units 113, a wheel assembly 12, two tubular sleeves 13, two slide rods 14, two link rods 15, and two pedal members 151. The main frame 11 includes an upstanding support 111, and a base support 112 connected to the upstanding support 111. The base support 112 has a rear end provided with two parallel guide rails 114.
The swing units 113 are connected pivotally and respectively to two opposite sides of the upstanding support 111.
The wheel assembly 12 is disposed on a front side of the main frame 11, and includes a resistance wheel 121, a crank wheel 122, and two crank members 123 connected respectively to two opposite ends of a crankshaft of the crank wheel 122. The resistance wheel 121 is connected to the crank wheel 122 through a belt or a magnetic mechanism so as to provide resistance to rotation of the crank wheel 122.
The tubular sleeves 13 are sleeved slidably and respectively on bottom portions of the swing units 113. Each tubular sleeve 13 includes spaced-apart universal upper and lower connectors 131, 132 connected to a rear side of the corresponding tubular sleeve 13. The upper connector 131 is connected pivotally to a corresponding one of the crank members 123.
Each slide rod 14 includes a front section 144 having a front end connected pivotally to the corresponding crank member 123, an intermediate section extending rearwardly from a rear end of the front section 144 and secured with a pedal seat 141, and a rear section 142 extending rearwardly, curvedly, and downwardly from a rear end of the intermediate section and having a rear end provided with a roller 143 that is slidable forwardly and rearwardly along the corresponding guide rail 114.
Each link rod 15 has a front end connected pivotally to the lower connector 132, and a rear end connected pivotally to the pedal seat 141.
The pedal members 151 are mounted slidably and respectively on the pedal seats 141 of the slide rods 14.
With reference to FIGS. 2 and 3, when the user steps on the pedal members 151 and starts exercising by exerting a force on the pedal members 151 in an alternating manner, the front end of the front section 144 of each slide rod 14 moves along with the corresponding crank member 123 in a circular motion, and the rear end of the rear section 142 of each slide rod 14 moves forward and rearward along the respective guide rail 114 through the slidable engagement of the roller 143 with the respective guide rail 114. As a consequence, the user's feet travel in a generally elliptical track shown in FIG. 3. Simultaneously, each tubular sleeve 13 moves with the corresponding crank member 123 so as to cause the bottom portion of each swing unit 113 to swing reciprocally, thereby effecting exercise of the user's upper body when the user's hands grasp upper portions of the swing units 113.
Although the conventional elliptical exercise apparatus 1 can achieve its intended purpose, it produces an elliptical track that is long in a front-to-rear direction and narrow in a top-to-bottom direction. Hence, there are sharp turns at front and rear ends of the track such that the elliptical motion of the user's feet is not smooth.